{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "This system is used to investigate the lateral diffusion of 40 nm gold spheres tethered to biotinylated lipids through antibody - functionalized ligands ( single - stranded DNA or polyethylene glycol ) ."}
{"Chemical": ["polyethylene glycol"]}